Theoretical Study on Predicting the Performance of Steam Ejector by Analogy Method

At present, it is difficult to obtain steam with high pressure under conventional laboratory conditions, and there are certain operational risks in the production of high-pressure and high-temperature steam devices. In this paper, a method to predict the critical entrainment ratio of the steam ejector by using the critical entrainment ratio of the air ejector is proposed. According to the one-dimensional calculation model of the ejector, the parameters related to the critical entrainment ratio are derived. The mathematical relationship between the entrainment ratio and each parameter is found through the mathematical tool Matlab. The performance of the ejector with different working mediums is simulated and verified by Fluent. The research results in this paper show that the entrainment ratio of air and steam ejector is linear with the pressure ratio within a certain range of pressure ratio. Under this linear relationship, the experimental entrainment ratio of the air ejector can be used to predict the entrainment ratio of the steam ejector. In a certain linear range, the relative error between the entrainment ratio predicted by the method proposed in this paper and the simulation results is within 10%.